I use a small electric fuel pump, rated at about 60l an hour for a bit under 1A. There are loads on eBay etc.
I run this pump on average about 1hr day, but use it more when the tank is stirred up when sailing or if there is a rolly anchorage.It picks up from the very bottom of the tank. I have only had it installed 6 months, but my fuel looks cleaner. I have not measured the flow, but estimate the output about 50l an hour after going through the filter.
I think its better to try and keep the polishing system separate from the main fuel system if possible, although you might consider a diversion system so you can run the main engine from the fuel polishing system in an emergency.
The same pump will work as a priming pump, or emergency lift pump if you want.
Originally Posted by Capnblu
Well, it seems that racor fg 500 filters require 60 GPH flow to separate particulate and water properly.
I did some research on this when I installed my fuel polishing system. The consensus was that a slow flow rate provided as good if not better filtration and water separation than a high flow rate. There was some opinions that the “Turbo” spiral for water separation fuel may work better at a high rate, but this was discounted by those with specialist knowledge.